High-Power VFD & AC Drive Repair
Component-level repair for variable frequency drives and AC drives from 75kW to 2MW — cement, steel, mining, power generation, paper, and petrochemical industries. Pan India.
A 500kW drive failure on a cement kiln or steel mill conveyor is a crisis — not a maintenance task. Synchronics repairs high-power VFDs and AC drives at the component level — IGBT stacks, thyristor bridges, capacitor banks, gate driver boards — for every major brand from 75kW to 2MW, with full-load bank testing before return.
High-power VFDs and AC drives — those above 75kW and up to 2MW — are the workhorses of India's most energy-intensive industries. A 200kW ball mill drive in a cement plant, a 450kW induced draft fan VFD at a thermal power station, a 1.2MW main drive on a rolling mill, or an 800kW compressor drive in a petrochemical facility: when any of these fails, the entire production process halts. Replacement drives at this power rating take weeks to source, cost tens of lakhs, and often require infrastructure modifications. Synchronics provides India's most capable component-level high-power drive repair — covering IGBT stack replacement, thyristor bridge rebuild, DC bus capacitor bank restoration, gate driver board repair, and control system restoration for all major brands up to 2MW and beyond.
Diagnosis Guide
Common High-Power VFD & AC Drive Problems We Fix
Experiencing any of these symptoms? Our engineers have diagnosed and repaired thousands of these faults.
IGBT Stack Failure
OC trip, no motor output, gate fuse blown, drive locked out — common on high-power cement and steel plant drives
Single IGBT failure causes cascade failure across the stack. Root causes: gate drive timing mismatch, overcurrent from load fault, thermal runaway from cooling degradation
Thyristor Commutation Failure
DC drive trips, armature current spike, SCR overtemperature alarm, motor runs erratically
Thyristor reverse recovery failure from supply transients, gate trigger circuit degradation, cooling failure on high-current SCR assemblies in steel plant DC drives
DC Bus Capacitor Bank Degradation
UV trip at light load, bus voltage ripple visible on scope, increased motor noise and vibration at low speed
Electrolytic ageing accelerated by high ambient temperature in cement and steel plant environments. ESR rise causes bus instability under load cycling
Control Board Failure
Drive does not boot, parameters lost, no communication response from DCS
FPGA or DSP failure from power transient, EEPROM corruption from repeated power cycling, fibre optic transceiver failure on gate drive interface
Cooling System Failure
OH overtemperature alarm, drive shuts down at rated load, thermal protection trips
Water coolant pump failure on liquid-cooled high-power drives, fan impeller damage in dusty cement or mining environments, heatsink fin blockage
Input Transformer or Rectifier Fault
Drive does not energise, input fuse trips, no DC bus voltage on high-power drive
Input phase imbalance from grid, transformer winding fault on 6-pulse or 12-pulse input transformer, rectifier diode failure from voltage transient
How It Works
Our High-Power Drive Repair Process
A systematic, schematic-driven repair process — from receipt to dispatch.
Safe De-energise & Collection
High-power drives must be safely de-energised with DC bus fully discharged before removal. We provide detailed safe removal instructions. Collection arranged by specialist freight — high-power drives require proper packing and handling.
Incoming Inspection & Photography
Drive photographed and inspected for physical damage, burn marks, failed component indicators, and cooling system condition. DC bus residual voltage verified safe before opening. ERP-logged with job reference.
High-Voltage Isolation Test
Insulation resistance and dielectric strength tested on power devices, bus bars, and motor output before energisation. Confirms safe repair environment and identifies any insulation breakdown.
Component-Level Repair
IGBT stacks, thyristor bridges, capacitor banks, gate driver boards, and control electronics repaired at component level from our 2M+ inventory — including high-voltage devices up to 6500V/3600A ratings.
Low-Power Commissioning Test
Drive tested at reduced voltage and current before full-power testing — verifies gate drive timing, protection circuit response, and control board functionality without risk to output devices.
Full Load Bank Test & Return
Full-load test at rated current on our load bank with thermal imaging. Test data recorded and included in repair report. 6-month warranty issued. Specialist freight return to site.
Thorough Inspection
What We Inspect in Every High-Power Drive
Every unit goes through a comprehensive inspection checklist before and after repair.
IGBT / IGCT Power Stack
Input Rectifier / Thyristor Bridge
DC Bus Capacitor Bank
Gate Driver Board
Cooling System
The Synchronics Advantage
Why Choose Us for High-Power VFD & AC Drive Repair
Up to 2MW Repair Capability
We repair high-power AC drives, VFDs, and DC drives from 75kW to 2MW and beyond — including 690V class, 3.3kV, and 6.6kV medium-voltage drives used in heavy industry and utilities.
Full Load Bank Testing
Every repaired high-power drive is tested at rated output current on our load bank — not just functionally powered. Thermal imaging at operating temperature verifies heatsink performance and confirms reliable operation before dispatch.
Component Repair — Not Drive Replacement
A replacement 500kW drive costs ₹10–₹40 lakh and takes 8–20 weeks to source. Component-level repair by Synchronics costs a fraction, preserves your existing configuration, and returns the drive in 72 hours.
Industries Served
Where High-Power VFD & AC Drives Are Used
Cement & Clinker
Kiln main drive VFDs, ball mill drives, raw mill drives, ID/FD fan VFDs, cement pump drives — 200kW to 1.5MW range
Steel & Metals
Rolling mill main drives, DC thyristor drives for reversing mills, conveyor VFDs, ladle crane drives, fume extraction fan drives
Mining & Quarrying
Crusher motor drives, conveyor belt VFDs, ball mill and SAG mill drives, winder and hoist drives, slurry pump VFDs
Power Generation
Boiler feed pump VFDs, induced draft fan drives, forced draft fan VFDs, cooling tower fan drives, condenser pump VFDs — thermal and hydro plants
Paper & Pulp
Paper machine main drives, refiner motor VFDs, chip conveyor drives, headbox pump drives, dryer section drives — 100kW to 800kW
Petrochemicals
Compressor motor VFDs, booster pump drives, crude pump inverters, heat exchanger fan control, cooling water pump drives
Trusted Brands
Brands We Service
Component-level repair for all major manufacturers
FAQ
Frequently Asked Questions
We repair AC drives, VFDs, and DC drives from 75kW up to 2MW and beyond, including 690V class drives and medium-voltage drives operating at 3.3kV and 6.6kV. Our high-power test bench and load bank facility support full-rated-current testing for all these ratings.
We provide detailed safe de-energisation and packing instructions specific to your drive model. Ensure DC bus capacitors are fully discharged (typically 5–15 minutes after power-off for high-power drives) before removal. We can arrange specialist freight collection for large and heavy drives — contact us for logistics coordination.
Yes. We repair medium-voltage drives operating at 3.3kV and 6.6kV used in power plants, water treatment, mining, and large industrial motor applications. Medium-voltage drive repair requires specific high-voltage handling procedures and component sourcing — our team is experienced in these requirements.
High-power drives typically require 72–96 hours for component-level repair plus full load bank testing. This compares to 8–20 weeks for a replacement drive sourced from Europe or Asia. We will provide a specific timeline estimate after initial diagnosis of your drive.
Yes. Many high-power drives installed in the 1990s and 2000s are no longer supported by their manufacturers. We repair these legacy high-power drives — including GEC, Eurotherm, Emerson, and older ABB/Siemens units — using our component inventory and circuit schematics. See also our dedicated Discontinued Drive Repair page.
High-Power VFD and AC Drive Repair — 75kW to 2MW, Pan India
Synchronics Electronics Private Limited provides India's most capable component-level repair service for high-power VFDs, AC drives, and DC thyristor drives from 75kW to 2MW. We serve cement plants, steel mills, mining operations, thermal power stations, paper mills, and petrochemical facilities across India — with pan-India courier and freight collection, 72-hour repair turnaround, and full-rated-current load bank testing on every repaired drive.
High-power drive repair requires capabilities unavailable at standard electronics repair workshops: high-voltage insulation testing, matched IGBT stack replacement at 1200V–6500V ratings, thyristor bridge rebuild for SCR-based DC drives, large capacitor bank restoration, and load bank testing at hundreds of kilowatts. Synchronics has made these capabilities available to Indian industry for over 32 years — at a fraction of drive replacement cost and a fraction of OEM sourcing lead time.
Get Your Equipment
Back in Action — Fast
Send us your faulty industrial electronics. Our engineers will diagnose it and provide a detailed quote within 24 hours — with no obligation to proceed.
Free Evaluation
No obligation
48hr Turnaround
Fastest in India
6-Month Warranty
Every repair
No Fix, No Charge
Zero risk policy
Pan-India Pickup
Doorstep service